kubectl Quick Reference

Fast commands for inspecting and operating Kubernetes resources.

Contexts and Namespaces

# Current context
kubectl config current-context

# List contexts
kubectl config get-contexts

# Switch context
kubectl config use-context <context>

# Set default namespace for current context
kubectl config set-context --current --namespace <ns>

# One-off namespace
kubectl -n <ns> get pods

Get and Inspect

# Get resources
kubectl get nodes
kubectl get ns
kubectl get pods
kubectl get deploy,sts,ds
kubectl get svc,ing
kubectl get events --sort-by=.metadata.creationTimestamp

# Wide output / labels
kubectl get pods -o wide
kubectl get pods --show-labels

# Describe (good for debugging)
kubectl describe pod <pod>
kubectl describe deploy <deploy>

# YAML/JSON
kubectl get deploy <deploy> -o yaml
kubectl get pod <pod> -o json

Logs and Exec

# Logs
kubectl logs <pod>
kubectl logs -f <pod>
kubectl logs <pod> -c <container>
kubectl logs --since=10m <pod>

# For Deployments/ReplicaSets (pick a pod automatically)
kubectl logs -f deploy/<deploy>

# Exec
kubectl exec -it <pod> -- sh
kubectl exec -it <pod> -c <container> -- sh

Create / Apply / Delete

# Apply manifests
kubectl apply -f k8s/
kubectl apply -f app.yaml

# Server-side apply (useful for GitOps-style ownership)
kubectl apply --server-side -f app.yaml

# Diff before applying
kubectl diff -f app.yaml

# Delete
kubectl delete -f app.yaml
kubectl delete pod <pod>

# Force delete a stuck pod (use carefully)
kubectl delete pod <pod> --grace-period=0 --force

Rollouts (Deployments)

# Watch rollout
kubectl rollout status deploy/<deploy>

# History and rollback
kubectl rollout history deploy/<deploy>
kubectl rollout undo deploy/<deploy>
kubectl rollout undo deploy/<deploy> --to-revision=<n>

# Restart (triggers a new ReplicaSet)
kubectl rollout restart deploy/<deploy>

Port Forward and Proxy

# Port-forward to a pod
kubectl port-forward pod/<pod> 8080:80

# Port-forward to a service
kubectl port-forward svc/<svc> 8080:80

# kubectl proxy (API server local endpoint)
kubectl proxy

Patch, Scale, and Edit

# Scale
kubectl scale deploy/<deploy> --replicas=3

# Edit live resource (writes back to the cluster)
kubectl edit deploy/<deploy>

# Patch (strategic merge)
kubectl patch deploy/<deploy> -p '{"spec":{"replicas":3}}'

# Set image
kubectl set image deploy/<deploy> <container>=<image>:<tag>

Labels and Annotations

kubectl label ns <ns> owner=team-a
kubectl label pod <pod> app=web --overwrite

kubectl annotate deploy/<deploy> kubernetes.io/change-cause="bump image"

Troubleshooting Recipes

# What's broken right now?
kubectl get pods -A
kubectl get events -A --sort-by=.metadata.creationTimestamp

# Find pods for a deployment
kubectl get pods -l app=<label>

# Show pod IP and node
kubectl get pod <pod> -o wide

# See why a pod is pending (look for events)
kubectl describe pod <pod>

# Debug DNS from an ephemeral pod
kubectl run -it --rm dns --image=busybox:1.36 --restart=Never -- sh
nslookup kubernetes.default

Output Filtering

# JSONPath examples
kubectl get pod <pod> -o jsonpath='{.status.podIP}{"\n"}'
kubectl get pods -o jsonpath='{range .items[*]}{.metadata.name}{"\t"}{.status.phase}{"\n"}{end}'

# Custom columns
kubectl get pods -o custom-columns=NAME:.metadata.name,NODE:.spec.nodeName,PHASE:.status.phase

Auth and RBAC

# Can I do X?
kubectl auth can-i get pods
kubectl auth can-i create deploy -n <ns>
kubectl auth can-i '*' '*' -n <ns>

Kustomize

# Built-in kustomize support
kubectl apply -k ./overlays/dev
kubectl diff -k ./overlays/dev